Germany / UK – In partnership with trailer refrigeration specialist, Thermo King Corp of Galway, Ireland, axle and suspension manufacturer, BPW Group of Wiehl, Germany, has been developing a new axle module, called ePower, for recovering energy from the trailer axles while braking and converting it to electricity to power a refrigeration unit. This project began five years ago and is now ready for series production; this article covers the development of this new product and how the partners plan to bring it to market for the benefit of the refrigerated transport vehicle sector.

This of course comes in the wake of increasingly stringent environmental regulations such as the upcoming Euro VII emissions standard in 2025 and the ban on red diesel in the UK. These have caused major distribution and logistics challenges across all major European cities as pollution and CO2 emissions continue to rise due to the growth in urbanisation, which is coupled with more restrictive loading and unloading periods in metropolitan areas and the aforementioned emissions targets. Combined, these factors are causing major headaches in the goods distribution industry.

Thermo King and BPW History

Five years ago, the companies came together to combine their research and development expertise to transform the way refrigerated trailers are powered using a more environmentally friendly approach. This leverages both companies’ respective expertise.

Founded in 1938, Thermo King is a brand of refrigeration and heating systems primarily used in the transportation industry. The company specialises in providing temperature control solutions for a wide range of applications, including trucks, trailers, buses, and marine containers. Thermo King is a division of Trane Technologies, a global multinational climate technology company that builds products which help ensure the safe transportation of perishable goods, such as food, pharmaceuticals, and other temperature-sensitive items.

BPW on the other hand, is a German company that focuses on the development and production of axles and suspension systems for commercial vehicles. Founded in 1898, BPW is best known for their axles, air suspensions, brake systems, and various components related to the running gear and chassis of commercial vehicles. The company has a reputation for innovative and high-quality products that are designed to enhance the performance, efficiency, and safety of commercial vehicles. They have been pioneers in introducing technologies such as disc brakes, intelligent trailer telematics systems, and eco-friendly solutions.

Therefore, the marriage between these two companies is one of convenience as Thermo King has been responsible for leveraging its temperature control technology, whilst BPW has offered its cutting-edge axle expertise in developing this new product.

Commenting on the necessity of the partnership in 2021, Thore Bakker, general manager of Trailer Solutions & Mobility Services at BPW, added: "Together with Thermo King, BPW is addressing the urgent problems of refrigerated transport, whose refrigeration units are still powered by a separate diesel engine today. By combining our competencies as technology leaders for freight transport solutions we can make temperature control systems more environmentally friendly through new energy concepts in the trailer. This will also have a positive implication to the Total Cost of Ownership of the freight forwarder along the transportation supply chain."

The project

Truck & Bus Builder had the opportunity to interview Glyn Davies, Sales Director at BPW and David O'Gorman, Commercial Director of North and Western Europe at Thermo King, a brand of Trane Technologies, who were both working closely on the project.

Since autumn 2019, the companies say they have worked together to create a sustainable power solution for refrigerated trailers, which, they state “will not only be environmentally friendly but also bring transport companies substantial cost savings.” The companies are on the cusp of delivering to market a reliable and efficient solution making zero-emission trailer transport refrigeration a reality.

Glyn Davies says that the project has been developed under BPW’s eSolutions division with BPW taking care of the axle including generators and the intelligent software control (energy management).

The new AxlePower energy recovery trailer refrigeration system has been created using BPW’s ePower axle. AxlePower is a fully integrated energy recovery system for powering a cooling unit with onboard battery storage, creating an autonomously powered refrigerated trailer. The system stores the energy generated while the vehicle is rolling or braking in a high-voltage battery and reuses it to power the refrigeration unit and keep the cargo at optimal temperature, perfect for the supermarket industry. The AxlePower system is completely independent of the tractor unit and is compatible with all Thermo King trailer refrigeration units. Therefore, the product delivers immediate sustainability benefits while also helping cut day-to-day operating costs.

How it works, the nuts and bolts

When asked how the ePower Axle works and the comparative advantages with other systems, the response from Glyn Davies was that the principle is similar to a bicycle dynamo that generates power for bicycle lights out of the movement of the turning wheel. The energy is then stored in a battery and supplied to the refrigeration unit, when required. The selling point to customers is based on energy efficiency and reducing emissions. This system will utilise 4 different generator modes that reduce energy redundancy (i.e., no lost or wasted power) with calculated savings of up to 4000 litres of fuel and up to 10t of CO2 per year based on an intelligent management system to control each generator.

These 4 different generator modes include: the Active mode, where the generator produces electric energy depending on the power demand and driving situation. Secondly, the Active Fast Charge mode which continuously produces electric energy with full power until the battery is almost fully charged. The environmentally friendly mode, Recuperation Only, uses the axle generator which produces electric energy by recuperation only, for instance when the vehicle is braking, which avoids additional fuel consumption of the towing vehicle. Finally, the Passive mode is when the axle generator does not produce electrical energy at all and remains on standby. All of these modes will be able to be controlled from inside the cab using a telematics system allowing the driver to monitor energy consumption, any error diagnostics and monitor the battery status. Of course, this product is fit for the aftermarket segment as the Axle Power System has utilised a modular design to fit on every trailer chassis.

Next Steps

The ePower axle will be produced in Wiehl, Germany, with series production slated to begin in October this year. When asked what the plans were for the next 12 months, Glyn Davies responded: “ We aim to launch a reliable system for markets in Europe, Australia, and South Africa, that includes an intelligent energy management system to safe fuel and maintenance costs.” Currently, testing in Sweden continues as the results from these various tests are being assessed.